Nami is the navigator of the Straw Hat Pirates and one of the most crucial members of Luffy's crew. She aims to draw a chart of all the oceans in the world one day and, for that, she will have to find the way to Laugh Tale.
While Nami is among the weakest members of the crew, she still has a significant amount of power up her sleeve. Recently, in Wano, she got her hands on Zeus, a homie of Big Mom. However, if Nami were to gain a Devil Fruit power, she would grow even stronger. There are some Devil Fruits that fit her more than others.
5 Soru Soru no Mi
The Soru Soru no Mi is one of the strongest Devil Fruits to exist in the One Piece world. It was eaten by none other than the former Yonko, Charlotte Linlin. This Devil Fruit is extremely overpowered as it allows the user to control souls at will. The user can snatch souls and, by virtue of that, the lifespan of people around them as long as they are feared.
At the same time, the user can also use their own soul to create powerful homies. These homies follow every single order of the user. They can also bring inanimate objects and even elements such as fire, or lightning to life. This Devil Fruit would be perfect for Nami as she would be allowed to create as many homies as she would like.
4 Mero Mero no Mi
The Mero Mero no Mi is another Paramecia type of Devil Fruit that is currently being used by Boa Hancock, the Pirate Empress. This Devil Fruit is extremely overpowered as it allows the user to turn to stone anyone who is either attracted by the user, or finds them likable. Furthermore, it can also turn an inanimate object into stone by making physical contact with them through techniques such as Perfume Femur or Slave Arrow.
This Devil Fruit would make Nami one of the scariest pirates on the seas, just as Boa Hancock is currently. Its powers would be immense and it would be extremely difficult to take her down in battle. Nami is already among the prettiest people alive in the world and she would be able to make full use of that in battle if she were to eat this Devil Fruit.
3 Goro Goro no Mi
The Goro Goro no Mi is a Logia type of Devil Fruit that is currently being used by Enel, the former God of Skypiea. This Devil Fruit is known to be one of the five considered to be invincible and, as such, its powers are tremendous. It allows the user to control, turn into, and produce lightning at will. The power of lightning is fearsome in the One Piece world and Nami already commands it through Zeus.
While Zeus is certainly extremely overpowered, capable of being a Yonko's weapon, the Goro Goro no Mi is simply superior. According to Oda, if Nami were to ever eat a Devil Fruit, it would be this one and that alone is proof enough that this powerful lightning Logia would be perfect for her. It would easily make Nami one of the most faired pirates on the seas and give her a great reputation, along with an exceptionally high bounty that could potentially even cross the billions.
2 Goru Goru no Mi
The Goru Goru no Mi is a Paramecia type of Devil Fruit that was introduced to the fans in One Piece Film Gold. This Devil Fruit was eaten by Tesoro, the antagonist of the movie, and it allowed him to telekinetically manipulate any gold that he had touched. This fruit also allowed the user to manipulate the state of gold and change between solid and liquid forms with ease.
When used properly, it made Tesoro powerful enough to compete with fighters such as Luffy in his Gear 4th. Nami, as fans know, loves gold more than almost everything in her life. For her, this Devil Fruit would certainly be perfect and it would complement her character as well, since her biggest obsession would become her biggest strength in battle. The only downside of this Devil Fruit is that it wouldn't allow her to produce gold and, thus, would require her to have a great amount of gold with her, or in her surroundings.
1 Uo Uo no Mi, Model: Seiryuu
The Uo Uo no Mi, Model: Seiryuu is easily among the very strongest Devil Fruits to exist in the One Piece world and it belongs to the former Yonko, Kaido of a 100 Beasts. This Devil Fruit allows the user to transform into a giant Eastern Dragon and its hybrid at will. While Nami doesn't particularly care for the dragon form that this fruit offers, it is the ability to manipulate the weather that would be extremely useful to her.
Nami uses the weather as her main weapon in One Piece, or at least she did until she got her hands on Zeus, the thundercloud homie. With the power of this Devil Fruit, Nami can manipulate not just lightning but also produce fire and control wind as well. It would make her more complete as a navigator/fighter and automatically boost her to be among the strongest pirates in the world of One Piece. At the same time, Nami is also physically very weak and this Devil Fruit would give her tremendous amounts of strength, along with the tough scales of a dragon that nearly nobody in the world can penetrate. Nami would, undoubtedly, be a feared pirate and her bounty would certainly skyrocket if she were to eat this Devil Fruit.